2008 F250 no fire on port side HELP PLEASE

RK

Petty Officer 2nd Class
Joined
Jun 27, 2006
Messages
107
Very slow idle. Sounds labored. Pulled injector wires one at a time on the port side make no difference. Starboard side seems fine. Tested for spark?... yes.... tested for fuel?.... yes...I see fuel spray out of the injectors when I pull the fuel rail. ... test for compression?... no I didn't yet.. but sure sounds good when I cranked with a spark plug out and it was a strong runner before the problem. I'm wondering if the variable valve timing is being an issue as it seems to have all 3 needed things to fire but isn't. I have the full shop manual but not sure where to start. Back story... I rebuilt the whole engine. Thrust bearing went bad. I've rebuilt many motors over the years. I took LOTS of pictures beforehand and took my time. I don't think there's anything mechanically wrong. I was VERY careful and got the belt and cams back exactly how it was. But once all back together something isn't right. If anybody with experience with these motors could walk be through some diagnostic items I'd surely appreciate it. I'm on vacation with family for the holidays in FL and it's a major bummer the boat is out of action. If i don't get this thing working the wife might force me to go shopping for T shirts and overpriced BS I don't need!!! Help!!!
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
9,092
good compression, good spark at the correct time, and the proper amount of fuel to air is necessary to burn properly,
testing it all is the only way to know for sure,
sounds like does not cut it
 

RK

Petty Officer 2nd Class
Joined
Jun 27, 2006
Messages
107
good compression, good spark at the correct time, and the proper amount of fuel to air is necessary to burn properly,
testing it all is the only way to know for sure,
sounds like does not cut it
Yea I know. I can dig up a compression tester. But I sort of doubt that's the issue for 3 cylinders not firing at all .. all on the same side. I'm going to do a compression check in the morning just to rule it out.
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
9,092
Yea I know. I can dig up a compression tester. But I sort of doubt that's the issue for 3 cylinders not firing at all .. all on the same side. I'm going to do a compression check in the morning just to rule it out.
then you need to be sure you have good spark at the proper time on all cylinders

proper fuel to air is hard to test
I am sure compression would say some about the valve timing
 
Last edited:

RK

Petty Officer 2nd Class
Joined
Jun 27, 2006
Messages
107
then you need to be sure you have good spark at the proper time on all cylinders

proper fuel to air is hard to test
I am sure compression would say some about the valve timing
Good point. Will check that and compare to the other side as well.
 

RK

Petty Officer 2nd Class
Joined
Jun 27, 2006
Messages
107
Cams installed the same way they came off. Is the valve timing adjustment 'off' at start?? That is to say... is the timing not adjusted by the ECM until much higher RPM than at idle?? 1734659896851.png
 
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